Doesn't matter what your OS. RAM and Processor Speed is what determines the most of your speed. A Mac with 128MB RAM and, say, 500MHz Processor speed, wouldn't be half as fast as my laptop that is Windows XP with 1GB RAM, and 1.7 GHz Processor speed.
@DBoy.. Compadibity is not a word that exists anywhere.. Maybe looking for Compatibility? If so you messed that one up REAL bad.. Maybe have your mother go over the english sections, namely 3rd grade spelling, again..